Merge "Use adaptive CDN TTLs for page views"

includes/OutputPage.php

@@ -1933,6 +1933,36 @@ class OutputPage extends ContextSource {
 		$this->setCdnMaxage( $this->mCdnMaxage );
 	}
 
+	/**
+	 * Get TTL in [$minTTL,$maxTTL] in pass it to lowerCdnMaxage()
+	 *
+	 * This sets and returns $minTTL if $mtime is false or null. Otherwise,
+	 * the TTL is higher the older the $mtime timestamp is. Essentially, the
+	 * TTL is 90% of the age of the object, subject to the min and max.
+	 *
+	 * @param string|integer|float|bool|null $mtime Last-Modified timestamp
+	 * @param integer $minTTL Mimimum TTL in seconds [default: 1 minute]
+	 * @param integer $maxTTL Maximum TTL in seconds [default: $wgSquidMaxage]
+	 * @return integer TTL in seconds
+	 * @since 1.28
+	 */
+	public function adaptCdnTTL( $mtime, $minTTL = 0, $maxTTL = 0 ) {
+		$minTTL = $minTTL ?: IExpiringStore::TTL_MINUTE;
+		$maxTTL = $maxTTL ?: $this->getConfig()->get( 'SquidMaxage' );
+
+		if ( $mtime === null || $mtime === false ) {
+			return $minTTL; // entity does not exist
+		}
+
+		$age = time() - wfTimestamp( TS_UNIX, $mtime );
+		$adaptiveTTL = max( .9 * $age, $minTTL );
+		$adaptiveTTL = min( $adaptiveTTL, $maxTTL );
+
+		$this->lowerCdnMaxage( (int)$adaptiveTTL );
+
+		return $adaptiveTTL;
+	}
+
 	/**
 	 * Use enableClientCache(false) to force it to send nocache headers
 	 *

includes/page/Article.php

@@ -706,6 +706,10 @@ class Article implements Page {
 			}
 		}
 
+		# Use adaptive TTLs for CDN so delayed/failed purges are noticed less often.
+		# This could use getTouched(), but that could be scary for major template edits.
+		$outputPage->adaptCdnTTL( $this->mPage->getTimestamp(), IExpiringStore::TTL_DAY );
+
 		# Check for any __NOINDEX__ tags on the page using $pOutput
 		$policy = $this->getRobotPolicy( 'view', $pOutput );
 		$outputPage->setIndexPolicy( $policy['index'] );
@@ -715,7 +719,6 @@ class Article implements Page {
 		$this->mPage->doViewUpdates( $user, $oldid );
 
 		$outputPage->addModules( 'mediawiki.action.view.postEdit' );
-
 	}
 
 	/**

includes/page/CategoryPage.php

@@ -68,6 +68,10 @@ class CategoryPage extends Article {
 		if ( $title->inNamespace( NS_CATEGORY ) ) {
 			$this->closeShowCategory();
 		}
+
+		# Use adaptive TTLs for CDN so delayed/failed purges are noticed less often
+		$outputPage = $this->getContext()->getOutput();
+		$outputPage->adaptCdnTTL( $this->mPage->getTouched(), IExpiringStore::TTL_MINUTE );
 	}
 
 	function openShowCategory() {